Web Page Validation

Web page validation means that the elements of the web page have passed a validation process in which the code of the page was reviewed by a third party site, and that the page conforms to the rules established by the organization. The question you might ask is why is this important? By validating a web page, you are testing it against an industry standard. This is stating that best practices were utilized to create the web page. Also each different web browser company creates their browser with these standards in mind. Having a validated web page increases the chances that the web page will display correctly in each of the different web browsers.

XHTML Validation

The W3C XHTML 1.0 Validation button means that the web page in question identified itself as "XHTML 1.0 Strict" and that a successful formal validation was performed using an SGML or XML Parser (depending on the markup language used).

As the validation prcess returns, it quotes
Valid XHTML 1.0! To show your readers that you have taken the care to create an interoperable Web page, you may display this icon on any page that validates.

CSS Validation

The W3C CSS Validation button means that the web page in question validated that the Cascading Style Sheets (CSS) in (X)HTML documents or standalone for conformance to W3C recommendations.

As the validation process returns, it quotes
This document validates as CSS!
To show your readers that you've taken the care to create an interoperable Web page, you may display this icon on any page that validates.